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HLA-DR2 dose effect on susceptibility to multiple sclerosis and influence on disease course 总被引:7,自引:0,他引:7 下载免费PDF全文
Barcellos LF Oksenberg JR Begovich AB Martin ER Schmidt S Vittinghoff E Goodin DS Pelletier D Lincoln RR Bucher P Swerdlin A Pericak-Vance MA Haines JL Hauser SL;Multiple Sclerosis Genetics Group 《American journal of human genetics》2003,72(3):710-716
Models of disease susceptibility in multiple sclerosis (MS) often assume a dominant action for the HLA-DRB1*1501 allele and its associated haplotype (DRB1*1501-DQB1*0602 or DR2). A robust and phenotypically well-characterized MS data set was used to explore this model in more detail. A dose effect of HLA-DR2 haplotypes on MS susceptibility was revealed. This observation suggests that, in addition to the role of HLA-DR2 in MS, two copies of a susceptibility haplotype further increase disease risk. Second, we report that DR2 haplotypes modify disease expression. There is a paucity of benign MS and an increase of severe MS in individuals homozygous for DR2. Concepts of the molecular mechanisms that underlie linkage and association of the human leukocyte antigen (HLA) region to MS need to be revised to accommodate these data. 相似文献
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Hartung T;Human 《Alternatives to laboratory animals : ATLA》2002,30(Z2):49-51
The Limulus amoebocyte lysate (LAL) test has replaced about 80% of the use of the rabbit pyrogen test. Ideally, human-based in vitro tests are needed, to replace the remaining use of the rabbit test and the use of the LAL test. The progress of an EU-funded project is described, in which a number of in vitro tests, based on the human fever reaction are passing through a prevalidation study on the way to evaluation in a formal validation study. 相似文献
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Wood WB;NRC Committee on Programs for Advanced Study of Mathematics Science in American High Schools 《Cell biology education》2002,1(4):123-127
A recently released National Research Council (NRC) report, Learning and Understanding: Improving Advanced Study of Mathematics and Science in U.S. High Schools, evaluated and recommended changes in the Advanced Placement (AP), International Baccalaureate (IB), and other advanced secondary school science programs. As part of this study, discipline-specific panels were formed to evaluate advanced programs in biology, chemistry, physics, and mathematics. Among the conclusions of the Content Panel for Biology were that AP courses in particular suffer from inadequate quality control as well as excessive pressure to fulfill their advanced placement function, which encourages teachers to attempt coverage of all areas of biology and emphasize memorization of facts rather than in-depth understanding. In this essay, the Panel's principal findings are discussed, with an emphasis on its recommendation that colleges and universities should be strongly discouraged from using performance on either the AP examination or the IB examination as the sole basis for automatic placement out of required introductory courses for biology majors and distribution requirements for nonmajors. 相似文献
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Ducros V Demuth K Sauvant MP Quillard M Caussé E Candito M Read MH Drai J Garcia I Gerhardt MF;SFBC Working group on homocysteine. French Society for Clinical Biology 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,781(1-2):207-226
It is now widely accepted that increased total plasma homocysteine (tHcy) is a risk factor for cardiovascular disease. Hyperhomocysteinemia can be caused by impaired enzyme function as a result of genetic mutation or vitamin B (B(2), B(6), B(9), B(12)) deficiency. A lot of methods are now available for tHcy determination. High-pressure liquid chromatography (HPLC) with fluorescence detection are at present the most widely used methods but immunoassays, easier to use, begin to supplant in-house laboratory methods. In order to help with the choice of a main relevant homocysteine analytical method, the characteristics, performances and limits of the main current methods are reviewed. One major drawback among all these available methods is the transferability which is not clearly established to date. The impact of both inter-method and inter-laboratory variations on the interpretation of the tHcy results are discussed. 相似文献